The Linux kernel 4.9.x before 4.9.233, 4.14.x before 4.14.194, and 4.19.x before 4.19.140 has a use-after-free because skcd->no_refcnt was not considered during a backport of a CVE-2020-14356 patch. This is related to the cgroups feature.
https://bugzilla.redhat.com/show_bug.cgi?id=1868453
https://cdn.kernel.org/pub/linux/kernel/v4.x/ChangeLog-4.14.194
https://cdn.kernel.org/pub/linux/kernel/v4.x/ChangeLog-4.19.140
https://cdn.kernel.org/pub/linux/kernel/v4.x/ChangeLog-4.9.233
https://lists.debian.org/debian-lts-announce/2020/10/msg00032.html
https://lists.debian.org/debian-lts-announce/2020/10/msg00034.html
Source: MITRE
Published: 2020-09-10
Updated: 2021-01-20
Type: CWE-416
Base Score: 7.2
Vector: AV:L/AC:L/Au:N/C:C/I:C/A:C
Impact Score: 10
Exploitability Score: 3.9
Severity: HIGH
Base Score: 7.8
Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Impact Score: 5.9
Exploitability Score: 1.8
Severity: HIGH